Many methods for processing and analyzing samples involve the steps of heating, shaking, and applying a magnetic field to the samples such as for extracting target compounds from the samples. Conventionally, the three steps of heating, shaking, and applying a magnetic field are performed at three independent and separate stations, for example utilizing a shaker, a magnetic separation device, and a heater.
One example is a class of methods implementing the hybridization and purification of DNA from blood samples. A sample consisting of DNA carried in liquid buffer is provided in the sample container. Magnetic beads are added to the container. The magnetic beads may be functionalized as needed to allow the DNA molecules to bind to the beads. The container is then mounted to a shaker such as an orbital shaker. The shaker agitates the sample to obtain a homogenous mixture of the magnetic beads with the sample, enhancing the yield of DNA bound to the magnetic beads. After shaking, the sample is removed from the shaker and transported to a magnetic separation device. The sample is dispensed into a tube and the tube is mounted to a tube holder of the magnetic separation device. The magnetic separation device includes permanent magnets positioned near the side of the tube. The permanent magnets attract the magnetic beads to the side of the tube, thereby concentrating the magnetic beads at one region in the tube. The buffer is then removed from the tube and replaced with ethanol as a wash step. The sample is then transported back to the shaker, and the shaker is operated again to disperse the ethanol and the magnetic beads in the tube. The sample is then transported back to the magnetic separation device to again concentrate the magnetic beads. The foregoing steps of shaking and magnetic beads separation may be repeated one or more times. The sample is then removed from the magnetic separation device and transported to a heater block. Heating by the heater block evaporates the ethanol, and the magnetic beads are allowed to air-dry. The DNA may then be eluted from the magnetics beads by a suitable solvent wash step.
The conventional process of heating, shaking, and applying a magnetic field is disadvantageous. The presence of the three separate stations required for heating, shaking, and magnetic-based separation consumes excessive space on a workbench. The use of three separate stations requires samples to be manually handled and transported from one station to another station, which is time consuming and creates the potential for contamination of the samples. Accordingly, there is a need to address these problems.